The insufficient contact between two phases in the heterostructure weakens the coupling interaction effect, which makes it difficult to effectively improve the electrochemical performance. Herein, a Co-carbonate hydroxide@ Ni-metal organic frameworks (Co-CH@Ni-MOFs) composite with super uniform core-shell heterostructure is fabricated by adopting 1D Co-CH nanowires as structuredirecting agents to induce the coating of Ni-MOFs. Both experimental and theoretical calculation results demonstrate that the heterostructure plays a vital role in the high performance of the as-prepared materials. On the one hand, the construction of super uniform core-shell heterostructure can create a large number of interfacial active sites and take advantages of the electrochemical characteristics of each component. On the other hand, the heterostructure can increase the adsorption energy of OH- ions and promote the electrochemical activity for improving the reversible redox reaction kinetics. Based on the aforementioned advantages, the as-fabricated Co-CH@Ni-MOFs electrode exhibits a high specific capacity of 173.1 mAh g-1 (1246 F g-1 ) at 1 A g-1 , an ultrahigh rate capability of 70.3% at 150 A g-1 and excellent cycling stability with 90.1% capacity retention after 10 000 cycles at 10 A g-1 . This study may offer a versatile design for fabricating a MOFs-based heterostructure as energy storage electrodes.
Keywords: Co-carbonate hydroxide; core-shell heterostructures; metal organic frameworks (MOFs); supercapacitors; ultrahigh rate performance.
© 2022 Wiley-VCH GmbH.